How to mount several USB devices (camera + handy-drive)?
 

Hi,

First of all, I don't know if you have a word for someone who know less about Linux than a "newbie". I'm not a computing person and I have been using Linux for less than a month, so my apologies if what I ask is rather stupid or I am not giving the correct information.

I'm using Mandrake 9.0 and I'm trying to configure both a usb "handy-drive" and a digital camera (Nikon Coolpix 2100). I have managed to configure both, separately. I mean, the handy-drive has been working fine all the time. It was automatically recognized by Mandrake from the beginning.

Then, to set up the digital camera I followed the advice I found in some forum and added

/dev/sda1 /mnt/nikon vfat user,sync 0 0

to fstab. The camera worked great. But then the handy-drive was no longer there. I then added to fstab

/dev/sda1 /mnt/usbhd auto user 0 0

and when I mounted the camera I was accessing the handy drive files from the camera directory and viceversa. But at some reboot Mandrake added a /mnt/removable and most of the times I could only access the handy drive from any of the mount points.

I've read some documentation and help files around, but I'm not a technical person and don't seem to understand very well what the problem is (apart from me fiddling with stuff I don't know). I've seen some configurations with, say, /dev/sda, /dev/sdb... or /dev/sda1, /dev/sda..., etc. But in my /dev directory I can only see sda and sda1 files. I don't know (this is were you can see I'm pretty ignorant) whether I need to use a different /dev file for each device or not. And if this is the case, which one, or whether I need to add one. Or whether the problem is some other thing altogether.

I have the suspicion that my problem is a rather stupid one, because both devices work perfectly... I guess I just messed up with the usb ports and the computer cannot find the proper device.

By the way. I have four usb ports in my computer. Do I need to connect each device to the same port always? I've always done that, but I don't really know why.

I hope I'm not taking too much of your time with this stuff! Thanks

eneko

I believe that USB mass storage devices appear as sda,sdb in the order in which they're noticed by the system.

I believe it may be possible reconfigure this behaviour, but I am not sufficiently familiar with hotplug to suggest how.

You may want to configure your fstab simply such that you refer to /dev/sda1 as /mnt/removable_1 and /dev/sda2 as /mnt/removable_2 or similar.

Thank you for the reply!

In my /dev directory I just have a file named "sda" and one named "sda1" (which sometimes appears as "sda0" [?]). Can I just create /dev/sda2 myself, or is it something that should be automatic?

Some more details, in case they are needed:

My fstab file reads,

/dev/hda1 / ext3 defaults 1 1
none /dev/pts devpts mode=0620 0 0
/dev/hda3 /home ext3 defaults 1 2
none /mnt/cdrom supermount dev=/dev/scd0,fs=auto,ro,--,iocharset=iso8859-15,codepage=850,umask=0 0 0
/dev/sda1 /mnt/nikon vfat user,sync 0 0
/dev/sda1 /mnt/removable vfat noauto,user 0 0
/dev/hda6 /mnt/windows vfat iocharset=iso8859-15,codepage=850,umask=0,defaults 0 0
none /proc proc defaults 0 0
/dev/hda5 swap swap defaults 0 0

If I mount /mnt/nikon with KDiskFree I access in that directory the contents of my handy-drive (that is, the other USB device) from Konkeror. If I then mount /mnt/removable (which has been automatically added on boot) it gives the following error,

Called: mount /dev/sda1
mount: /dev/sda1 already mounted or /mnt/nikon busy
mount: according to mtab, /dev/sda1 is already mounted on /mnt/nikon

If then I unmount /mnt/nikon and mount /mnt/removable in turn, the /mnt/removable directory appears empty, but /mnt/nikon shows again the handy-drive files. That is, in both cases I can only access to the handy-drive.

I don't know if it is of any use, but my mntab file is,

/dev/hda1 / ext3 rw 0 0
none /proc proc rw 0 0
none /proc/bus/usb usbdevfs rw 0 0
none /dev devfs rw 0 0
none /dev/pts devpts rw,mode=0620 0 0
/dev/hda3 /home ext3 rw 0 0
none /mnt/cdrom supermount ro,dev=/dev/scd0,fs=auto,--,iocharset=iso8859-15,codepage=850,umask=0 0 0
/dev/hda6 /mnt/windows vfat rw,iocharset=iso8859-15,codepage=850,umask=0 0 0
/dev/sda1 /mnt/nikon vfat rw,noexec,nosuid,nodev,sync,user=eneko 0 0

Cheers,

eneko

That is certainly rather odd. I'm not sure what could be going on there.

Are you certain that you've seen sda0? That's not a node I've ever come across. At this point my unfamiliarity with Mandrake become a problem: I'm not sure how it handles device nodes. Is the output of "ls /dev/sd*" really just "/dev/sda /dev/sda1"? If there really are just those couple of nodes then I can't see how they'd exist without Mandy creating them automatically on detecting the device. But I don't know.

You may find it instructive to observe the changing output of dmesg, as you insert one of the devices in question, to see if the usb mass storage driver gives any instructive information about which SCSI device it's emulating.

Sorry :( . It was scd0, not sda0. Now I feel really stupid.

[root@streamyx /]# ls /dev/sd*
/dev/sda@ /dev/sda1@

/dev/sd:
c1b0t0u0@ c1b0t0u0p1@

I'm looking at it... Not that I can understand a line, but I'll try to find out the differences between outputs.